三价锑的电沉积机理  

Electrodeposition Mechanism of Trivalent Antimony

作　　者：林艳[1] 谢刚[2] 杨大锦[2] 

机构地区：[1]昆明理工大学冶金与能源工程学院,昆明650093 [2]云南冶金集团股份有限公司技术中心,昆明650031

出　　处：《有色金属（冶炼部分）》2011年第5期7-11,共5页Nonferrous Metals（Extractive Metallurgy)

基　　金：云南省科技攻关项目(2000KFZX-14)

摘　　要：采用恒电流阶跃法及交流阻抗法等电化学方法,研究了H2SO4-NH4F-SbF3体系中三价锑的阴极还原机理。电势~时间暂态曲线出现二步反应特征,表明Sb3＋还原分两步进行。由恒电流阶跃曲线中iτ1/2~i关系可知Sb3＋阴极还原存在前置化学转化。Sb3＋阴极还原的交流阻抗测定结果进一步验证Sb3＋还原是存在化学前置转化步骤的二步反应,且电活性中间产物吸附在电极表面,吸附反应对两步电子转移步骤的影响不同。The reduction mechanism of Sb3＋ in H2SO4-NH4F-SbF3 electrolyte system was studied by means of electrochemical methods,including chronopotentiometry and alternating current impedance.Analysis of potential-time transients clearly shows that antimony  could be reduced to antimony metal via two-steps irreversible electron transfer process in H2SO4-NH4F-SbF3 system.The relationship between iτ1/2and i calculated by chronopotentiometry indicates that the trivalent antimony complex undergoes chemical transformation reaction before its reduction in the cathode.The impedance results confirm the above conclusion and indicate that the adsorption states which are the middle product of trivalent antimony have different influences on two electron transfer steps.

关 键 词：H2SO4-NH4F-SbF3体系 锑 电化学动力学 

分 类 号：TF818[冶金工程—有色金属冶金]